The Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the Non-Proliferation Treaty or NPT, is a landmark international treaty whose objective is to prevent the spread of nuclear weapons and weapons technology, to promote cooperation in the peaceful uses of nuclear energy and to further the goal of achieving nuclear disarmament and general and complete disarmament. Opened for signature in 1968, the Treaty entered into force in 1970. On 11 May 1995, the Treaty was extended indefinitely. A total of 190 parties have joined the Treaty, including the five nuclear-weapon States: the United States, Russia, the United Kingdom, France, and China (also the five permanent members of the United Nations Security Council). More countries have ratified the NPT than any other arms limitation and disarmament agreement, a testament to the Treaty's significance. Four non-parties to the treaty are known or believed to possess nuclear weapons: India, Pakistan and North Korea have openly tested and declared that they possess nuclear weapons, while Israel has had a policy of opacity regarding its own nuclear weapons program. North Korea acceded to the treaty in 1985, but never came into compliance, and announced its withdrawal in 2003.

Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the Nuclear Nonproliferation Treaty or NPT.

Proliferation has been opposed by many nations with and without nuclear weapons, the governments of which fear that more countries with nuclear weapons may increase the possibility of nuclear warfare (up to and including the so-called "countervalue" targeting of civilians with nuclear weapons), de-stabilize international or regional relations, or infringe upon the national sovereignty of states.

Four countries besides the five recognized Nuclear Weapons States have acquired, or are presumed to have acquired, nuclear weapons: India, Pakistan, North Korea, and Israel. None of these four is a party to the NPT, although North Korea acceded to the NPT in 1985, then withdrew in 2003 and conducted announced nuclear tests in 2006 and 2009. One critique of the NPT is that it is discriminatory in recognizing as nuclear weapon states only those countries that tested nuclear weapons before 1968 and requiring all other states joining the treaty to forswear nuclear weapons.^{[citation needed]}

Tadatoshi Akiba (秋葉 忠利, Akiba Tadatoshi^?, born November 3, 1942 in Arakawa, Tokyo) is a Japanese politician and served as the mayor of the city of Hiroshima, Japan from 1999 to 2011.

He studied mathematics at the University of Tokyo, receiving a B.S. in 1966 and an M.S. in 1968. He continued his studies under John Milnor at the Massachusetts Institute of Technology, earning his PhD in mathematics in 1970. He took teaching jobs at a series of universities: State University of New York at Stony Brook (1970), Tufts University (1972–1986), and Hiroshima Shudo University (1986–1997). His research was on topology, with an interest in homotopy groups.

As a member of the Social Democratic Party, he was elected to the House of Representatives, and served from 1990 to 1999. He assumed office as mayor of Hiroshima in February, 1999, and was reelected to this position in 2003 and in April 2007.

As mayor, he has been a visible peace activist. He is active in the Mayors for Peace organization, serving as the president of their World Conference. The 2020 Vision Campaign launched in 2003, which aims to eliminate nuclear weapons, has earned Mayors for Peace the "World Citizenship Award" from the Nuclear Age Peace Foundation in 2004, the "Sean McBride" Award from the International Peace Bureau in 2006, and the Nuclear-Free Future Award from the Franz-Moll Foundation in 2007. He has also been an advocate of the abolition of nuclear weapons, and a vocal critic of George W. Bush. Since May 2007 he is also Councillor at the World Future Council.

Benjamin "Bibi" Netanyahu (Hebrew: בִּנְיָמִין "בִּיבִּי" נְתַנְיָהוּ (help·info); born 21 October 1949) is the current Prime Minister of Israel. He serves also as the Chairman of the Likud Party, as a Knesset member, as the Health Minister of Israel, as the Pensioner Affairs Minister of Israel and as the Economic Strategy Minister of Israel.

Netanyahu is the first Israeli prime minister born in Israel after the founding of the state. Netanyahu joined the Israeli Defense Forces during the 1967 Six-Day War, and became a team leader in the Sayeret Matkal special forces unit. He took part in many missions, including Operation Gift and Operation Isotope, during which he was shot in the shoulder. He fought on the front lines in the Yom Kippur War in 1973, taking part in special forces raids along the Suez Canal, and then leading a commando assault deep into Syrian territory. He achieved the rank of captain before being discharged. Netanyahu served as the Israeli ambassador to the United Nations from 1984 to 1988, member of the Likud Party, and was Prime Minister from June 1996 to July 1999.

Alyn Ware (born 1962) is a peace acivist from New Zealand. Formerly a vice president of the International Peace Bureau, he is the Global Coodinator of the Parliamentarians for Nuclear Non-Proliferation and Disarmament (PNND), a member of the World Future Council, and is engaged with several international organisations working against nuclear weapons. He was awarded the Right Livelihood Award in 2009.